What are permissions?

[Bigtree]

What would be the counter part in windows? What function do they provide?

 

[Sherman Homan]

They are simply the ability of the Mac's operating system to allow a user to read, write or delete a file or folder. The System can restrict access to essential files, another user can prohibit anyone else from seeing their files. Or a shared folder could be made available to anyone. The very foundation of the Unix roots of the OS X are based on this.